In May 1983, President Ronald Reagan asked me to lead the Environmental Protection Agency for a second time. The first time was when the EPA began. Reagan’s first appointed administrator, Anne Burford, had lost the trust of the public and the confidence of Congress. There were serious questions about the management of the EPA’s Superfund program and a too-cozy relationship with corporate executives and lobbyists.

On my first day back, I issued what is now called the “fishbowl memo,” which laid out my commitment to openness at the agency. We started to release my full schedule and the publication of written communications on a daily basis. We held regular, brown-bag lunches with the reporters who covered the agency, and every reporter knew he or she could attend. Every other Wednesday, I would spend 90 minutes meeting with those reporters, answering questions. Nothing was off-limits. Everything was on the record.

Why was this so important?

Because the EPA is a public-health agency that is just as important to people’s well-being as the Food and Drug Administration or the National Institutes of Health. The statutes the EPA administers are explicit and unmistakable: Set a safe level of exposure to (name your chemical or pollutant or pesticide) with an adequate margin of safety.

Is it safe to breathe this air? Is it safe to drink this water? Or to swim in it? Is that apple free of toxic chemicals? What is that old waste dump doing to the well water? These are the kinds of questions the EPA answers for the American people.

For the agency to be effective in protecting health, it must first be trusted. People have to believe that when the EPA says something is safe, it is. Otherwise we’ll have chaos.

People must believe the EPA is acting in their interest, the public interest, not on behalf of a special or influential interest. That’s why at a time of crisis for the EPA in 1983, the fishbowl memo was so important, why press access was so important.

Scott Pruitt, the current EPA administrator, is taking the absolute opposite approach.

Pruitt operates in secrecy. By concealing his efforts, even innocent actions create an air of suspicion, making it difficult for a skeptical public to give him the benefit of the doubt.

It’s not that Pruitt is meeting too frequently with executives and lobbyists from the industries he regulates. Every EPA administrator does that and should do that. But there should be a public record about what was discussed at the meetings. Any access to a specific interest should be matched by the same grant to all interests. Most often the public hearing process will satisfy any need for individual meetings.

Becoming an advocate for a specific industry raises serious questions that sow doubt about fairness and objectivity. The EPA should have no natural constituency but the public whose health it is mandated to protect.

Pruitt appears to be turning his back on a bipartisan tradition of transparent governance at the EPA. While no administration is perfect on this, Pruitt’s history of working intimately with industry makes it all the more important that he allay his critics’ fears instead of intensifying them. And the consequence of such conduct is the slow, destructive erosion of public trust in the EPA.

Once trust is lost and warnings of unsafe air or contaminated water are ignored, Americans will pay the price. Without that trust, not only will people question whether they can believe their government but also business and industry will face public backlash. Boycotts and other attacks are no good for industry and may result in more regulation than warranted.

Industry leaders understand that a public regulatory agency gives their businesses a public license to operate. A strong, credible and fair regulatory regime is essential to the smooth functioning of our economy. Unless people believe their health and the environment are being safeguarded, they will withdraw their permission for companies to do business.

To Pruitt and President Donald Trump, I suggest remembering Anne Burford’s experience at the EPA. Remember that a loss of public trust can come back to haunt your administration.

William D. Ruckelshaus was administrator of the Environmental Protection Agency from 1970 to 1973 and from 1983 to 1985.